Abstract: Dr. Karl Paley Cohen was a physicist and advisor involving nuclear energy and reactor development who began his career making
scientific advances in uranium production with the Manhattan Project at Columbia University in the 1940s. Working under Harold
Urey, Cohen developed the now universal method of centrifugal isotope separation for enriching uranium. While the collection
includes many declassified lab notebooks and journals from this time, it largely covers Cohen’s long period of service with
General Electric as well as various consultancies, and includes reports, correspondence, notes, and other material related
to nuclear electric power generation and its safety, economic viability, public policy and other concerns.

Access to Collection

Open for research. Note that material must be requested at least 36 hours in advance of intended use. Audiovisual materials
are not available in original format, and must be reformatted to a digital use copy.

Publication Rights

While Special Collections is the owner of the physical and digital items, permission to examine collection materials is not
an authorization to publish. These materials are made available for use in research, teaching, and private study. Any transmission
or reproduction beyond that allowed by fair use requires permission from the owners of rights, heir(s) or assigns.

Acquisition Information

This collection was given by Karl Cohen to Stanford University, Special Collections in 2010.

Biographical

Karl Paley Cohen (1913-2012) was born in New York City. He studied chemistry at Columbia University from 1929 to 1936, followed
by post-doctoral work in Paris (where he met his wife, Marthe-Hermance Cohen). Beginning in 1937 Cohen was research assistant
to professor Harold Urey, who had earned the 1934 Nobel Prize in Chemistry for his work on isotopes. As the war escalated,
Urey was named director of the Manhattan Project at Columbia, and Cohen was hired as head of the project’s Theoretical Division,
with the responsibility for determining processes for U-235 (uranium) isotope separation. Subsequently, Cohen was deeply involved
with perfecting the gaseous diffusion and centrifuge techniques for enrichment, and uranium sources and production would be
a major focus of his career.

In 1944 Dr. Cohen began working for Standard Oil, primarily studying the economics of the emerging nuclear energy industry.
Following this, Cohen was a technical director for H.K. Ferguson's Atomic Energy Division, responsible for the construction
of the Brookhaven nuclear reactor. By 1952, Cohen was a founder, vice president and operating manager of Walter Kidde Nuclear
Laboratories, a privately-funded research facility formed to commercially develop nuclear power. The lab’s principal contract
was with the Atomic Energy Commission for R&D on reactors, and established many industry standards, especially regarding slightly
enriched uranium and water moderated reactor concepts.

Cohen’s long association with General Electric began in 1956, at first as a consultant, then as a manager involved with advanced
engineering, advanced products, breeder reactor development, and operational planning. In 1973 Cohen was appointed Chief Scientist
of G.E.'s commercial nuclear department. After his retirement in 1978, Cohen consulted for companies such as G.E., Boeing,
and Exxon, and organizations such as the Institute for Energy Research, Scientists and Engineers for Secure Energy and the
Electric Power Research Institute. Cohen also continued to be active on committees, at conferences, and in more informal peer
review of technology and policy papers. He also taught intermittently at Stanford during this time. Karl Cohen passed away
after a long illness in 2012.

Cohen holds several patents in nuclear reactor technology and isotope separation, having developed the now universally-used
centrifuge method, and wrote the standard reference text "Isotope Separation" in 1945. He was elected to the National Academy
of Engineering in 1967 and served as president of the American Nuclear Society for 1968-1969.

Preferred Citation

[identification of item], Karl Cohen papers (M1798). Dept. of Special Collections and University Archives, Stanford University
Libraries, Stanford, Calif.

Scope and Contents

The papers of Karl Cohen include reports, papers, articles, notes, memoranda and correspondence, primarily related to nuclear
power generation. The collection has been divided into fourteen series. Cohen's own work, with some declassified items dating
from the 1930s and 40s, is contained for the most part in Series 1-4, although his student notebooks are in Series 9, and
scientific reprints in Series 11. There are also media-specific series here for photographs, slides, and audiovisual material.
The subject file series has been arranged alphabetically, and represent companies, organizations, countries, technical processes,
and concerns (such as forecasting, economics, proliferation, and safety) which featured heavily in Cohen’s career.

Subjects and Indexing Terms

Nuclear energy.

Nuclear reactors

General Electric Company.

Cohen, Karl P.

Cohen, Karl P.

Manhattan Project (U.S.)

Urey, Harold Clayton

1. Cohen papers1939-1992

Scope and Contents

Material created and chronologically arranged by Cohen, including scientific papers, lectures, articles, reports, notes, memoranda,
correspondence, transcripts, and prepared testimony. Wartime documents were declassified in 1972. Some are copies and appear
related to legal research, possibly for patents. 1939-1940 files are all reprints. There are no files for 1990 and 1991. Other
work by Cohen can be found throughout the collection.

1939-1940

box 7, folder 11

Papers

box 7, folder 12

Dunning Claim1940-1962

box 8, folder 1

Declassified Reports M-446, M-1340, M-1342 [etc., contains list]

box 8, folder 2

ALSOS/DIV IV1944

1945-1952

box 8, folder 3

Esso [Laboratories, part of Standard Oil]

box 8, folder 4

talks, papers, seminar

box 8, folder 5

AEC Consulting

box 8, folder 6

Slightly Enriched Reactors

1952-1956

box 8, folder 7

Investment in Atomic Energy - Prospectus for Development Company1952

box 8, folder 8

Brookhaven and AEC Consulting1948-1956

box 8, folder 9

papers, talks

1956-1965

box 8, folder 10

papers, talks, correspondence1958-1968

box 8, folder 11

Speeches to 1965

1966-1975

box 9, folder 1, box 9, folder 2

papers

box 9, folder 3

Correspondence to 1976

box 10, folder 1

Speeches

1976

box 10, folder 2

papers

box 10, folder 3

JCAE (Joint Committee on Atomic Energy)Testimony1976-02

1977

box 10, folder 3

papers

1978

box 10, folder 4

Oregon Paper

box 10, folder 5

papers

box 10, folder 6

IIASA Drafts

1979

box 10, folder 7

papers

1980

box 11, folder 1

papers

1981

box 11, folder 2

papers

1982

box 11, folder 3

papers

1983

box 11, folder 4

papers

box 11, folder 5

Urey

1984

box 11, folder 6

papers

box 11, folder 7

Front End of the Fuel Cycle

box 11, folder 8

Privatization1984-1986

1985

box 11, folder 9

presentation with slides

1986

box 11, folder 10

papers

box 11, folder 11

Phoenix Forum

box 12, folder 1

Saratoga Paper

1987

box 12, folder 2

papers

1988

box 12, folder 3

papers

1989

box 12, folder 4

ANS Fuel Cycle

1992

box 12, folder 5

papers

2. Cohen writing1931-2001

Scope and Contents

Miscellaneous work by Cohen, including papers, lectures, and other writing, arranged chronologically.

box 6, folder 2

untitled presentation [draft with notes and transparencies]

box 16, folder 4

"A Modest Proposal" school paper1931

box 7, folder 10

Thesis1936-1938

box 41, folder 4

MIT Lecture1947

box 6, folder 4

The Future of Nuclear Energy [draft manuscript of presentation]1969

box 6, folder 3

Science Article [Cohen breeder reactors article with notes]1970

box 6, folder 5

Berkeley Seminars1970

box 7, folder 8

Urey Biography material1983

box 7, folder 9

Urey Biography. The War Years 1939-1944 [draft typescript]1983-03-21

box 22, folder 7

quantum mechanics paper, etc. [labeled AIF Phoenix 86]

box 22, folder 3, box 22, folder 4

Think Pieces 70s-80s [mainstream/popular articles with notes]

box 56, folder 6

Techsnabexport notebookcirca 1970s

box 46, folder 6

Issues Affecting Nuclear Power in the Next Century (BNES "Nuclear Energy" reprint)2001

These files (including correspondence, reports, meeting minutes, and journals) had been kept in a safe at the General Electric
library prior to release to Cohen, but much of it pre-dates his employment there. Folders were originally organized in two
numerical sequences, but contain significant gaps. Some itemized lists are enclosed.

box 2, folder 1

lists and miscellaneous

box 2, folder 4

1.02 Correspondence from AEC1959-1967

box 2, folder 5

1.23 Gas Characteristics - AEC1955-1956

box 2, folder 6

2.56.01 General Correspondence Consultants1962-1964

box 2, folder 7

2.57 Proposals1962-1964

box 2, folder 8

7.16 Mass Flow - Foreign1959-1960

box 2, folder 9

9.01 Correspondence to KPC1959-1964

box 2, folder 10

9.02 Correspondence to KPC1960-1967

box 2, folder 11

9.08 General Calculation Methods - KPC1951-1958

box 2, folder 12

11.01 Correspondence to Allied1962-1967

box 2, folder 13

11.02 Correspondence from Allied1962-1965

box 2, folder 14

11.53 Allied - Security1963

box 2, folder 15

11.90 Allied - Economics1961-1965

box 3, folder 1

2. Secret1958

box 3, folder 2

5. Chicago Reports1943-1944

box 3, folder 3

6. Washington Reports1944-1946

box 3, folder 4

8. Columbia Reports1944-1945

box 3, folder 5

10. Reactor Physics Planning Group (RPPG)1954-1955

box 3, folder 6

11. RPPG Second Meeting1955

box 3, folder 7

13. RPPG Fourth Meeting1951-1962

box 3, folder 8

14. RPPG Fifth Meeting1954

box 3, folder 9

16. KPC Patent, Pre-WKNL1950-1961

box 3, folder 10

17. W.O.1492C Reports1951-1962

box 3, folder 11

18. Baird Associates Proposal1952

box 3, folder 12

22. Contract W-7405-ENG-501944-1945

box 3, folder 13

23. Information Meetings [draft report from Oak Ridge]

box 3, folder 14

24. OEMsr-4121941-1943

box 3, folder 15

26. E. Teller - Slightly Enriched Reactor1949-1950

box 3, folder 16

27. WO-13841950

box 3, folder 17

30. OA-LXXX-729-3A TS-10501951

box 17, folder 1

1002. Legislative, Governmental Control and Commissions - Public Policy (Pre-MacMahon)1945-1946

box 3, folder 8

Dr. Irving Kaplan S.A.M. Lab notebook

box 17, folder 6

Columbia lab notebook1940

5. correspondence1978-2000

Scope and Contents

Incoming correspondence as well as some outgoing drafts and copies, arranged chronologically. Also includes memoranda and
some printed email.

AIF International Conference on Uranium Enrichment. New Orleans, Louisiana1978

AIF Fuel Cycle Forum. Atlanta, Georgia1984

box 52, folder 3

brochures, reports1984

box 52, folder 2

Conference Papers1984

box 16, folder 2

AIF Fuel Cycle Conference. Scottsdale, Arizona1986

box 16, folder 1

AIF "Enrichment Marketplace in the 1990's" Conference, San Francisco, California1987

8. subject files

Scope and Contents

The subject file series was created to group all of Cohen's files related to his consultancies, special projects, technical
processes and developments, and overall concerns within the nuclear power industry (such as proliferation). Most files related
to his work at G.E. are contained here.

1. American Nuclear Society (ANS)

Subjects and Indexing Terms

American Nuclear Society

box 34, folder 7

Policy Statements1979-1987

box 55, folder 2

directories1973, 1999

box 33, folder 5, box 33, folder 4

China trip1980

box 33, folder 6

China trip - Photographs and Slides1980

2. Atomic Industrial Forum, Inc. (AIF)

Subjects and Indexing Terms

Atomic Industrial Forum

box 12, folder 6

AIF Committee1977-1982

box 13, folder 2, box 13, folder 1

AIF Technical Papers1977-1978

box 23, folder 1

AIF Committee 87 [reports, articles]1982-1992

box 48, folder 1

AIF Committee [Subcommittee on Enrichment]1983-1985

box 48, folder 2

AIF Committee [Subcommittee on Enrichment] - Correspondence1983-1985

3. Boeing

Scope and Contents

Cohen consulted for Boeing on gas centrifuge enrichment and privatization.